The Mean Time To Production (MTTP) benchmark measures the time it takes for Flux to deploy application changes into production. We measure the time spent on fetching app packages from the registry (Flux OCI artifacts and Helm charts) and the time spent reconciling app definitions on the Kubernetes cluster.
For this benchmark we assume 100, 500 and 1000 app packages being pushed to the registry at the same time.
Specs
- GitHub hosted-runner (ubuntu-latest-16-cores)
- Kubernetes Kind (3 nodes)
- Flux source-controller (1CPU / 1Gi / concurrency 10)
- Flux kustomize-controller (2CPU / 1Gi / concurrency 20)
- Flux helm-controller (2CPU / 1Gi / concurrency 10)
- Helm repository (oci://ghcr.io/stefanprodan/charts/podinfo)
- App manifests (Deployment scaled to zero, Service Account, Service, Ingress)
| Objects | Type | Flux component | Duration | Max Memory |
|---|---|---|---|---|
| 100 | OCIRepository | source-controller | 25s | 38Mi |
| 100 | Kustomization | kustomize-controller | 27s | 32Mi |
| 100 | HelmChart | source-controller | 25s | 40Mi |
| 100 | HelmRelease | helm-controller | 28s | 190Mi |
| 500 | OCIRepository | source-controller | 45s | 65Mi |
| 500 | Kustomization | kustomize-controller | 2m4s | 134Mi |
| 500 | HelmChart | source-controller | 45s | 68Mi |
| 500 | HelmRelease | helm-controller | 2m45s | 250Mi |
| 1000 | OCIRepository | source-controller | 1m30s | 67Mi |
| 1000 | Kustomization | kustomize-controller | 4m15s | 190Mi |
| 1000 | HelmChart | source-controller | 1m30s | 110Mi |
| 1000 | HelmRelease | helm-controller | 8m1s | 490Mi |
Compared to Flux v2.2, in this version the memory consumption of the helm-controller has improved a lot, especially when the cluster has hundreds of CRDs registered. In Flux v2.2, helm-controller on Kubernetes v1.28 is running out of memory with 100 CRDs registered, while in Flux v2.3 on Kubernetes v1.29 it can handle 500+ CRDs without issues. Given these results, it is recommended to upgrade the Kubernetes control plane to v1.29 and Flux to v2.3.
| Objects | Type | Flux component | Duration | Max Memory |
|---|---|---|---|---|
| 100 | OCIRepository | source-controller | 25s | 38Mi |
| 100 | Kustomization | kustomize-controller | 27s | 32Mi |
| 100 | HelmChart | source-controller | 25s | 40Mi |
| 100 | HelmRelease | helm-controller | 31s | 140Mi |
| 500 | OCIRepository | source-controller | 45s | 65Mi |
| 500 | Kustomization | kustomize-controller | 2m2s | 72Mi |
| 500 | HelmChart | source-controller | 45s | 68Mi |
| 500 | HelmRelease | helm-controller | 2m55s | 350Mi |
| 1000 | OCIRepository | source-controller | 1m30s | 67Mi |
| 1000 | Kustomization | kustomize-controller | 4m15s | 112Mi |
| 1000 | HelmChart | source-controller | 1m30s | 110Mi |
| 1000 | HelmRelease | helm-controller | 8m2s | 620Mi |
Increasing kustomize-controller's concurrency above 10 does yield better
results, but the /tmp directory must be in tmpfs to prevent the Kustomize
build from disk thrashing. Documentation on this can be found here:
https://fluxcd.io/flux/installation/configuration/vertical-scaling/#enable-in-memory-kustomize-builds
Increasing helm-controller's concurrency above 10 does not yield better results due to Helm SDK overloading the Kubernetes OpenAPI endpoint. Higher concurrency probably requires an HA Kubernetes control plane with multiple API replicas.